1. Field of the Invention:
The present invention relates to a mobile communication system. More particularly, the present invention relates to an apparatus and a method for providing an adaptive multimedia service in a mobile communication system.
2. Description of the Related Art:
A multimedia service refers to a conversational service such as a video telephony service, a streaming service such as a Video On Demand (VOD) service, a multicast service, a broadcast service, and the like. Meanwhile, a real time multimedia service can be divided into the conversational service, an interactive service, and the streaming service according to a service type. Further, the real time multimedia service can be divided into a unicast service, the multicast service, and the broadcast service according to a number of participants in a service.
Here, in order to support multimedia services such as the conversational service and the VOD service, Quality of Service/Quality of Experience (QoS/QoE) should be adaptively controlled according to a network state. Network-aware information for supporting such a multimedia service may contain an available bit-rate, a packet loss ratio, a delay, a jitter, information on a state of a router buffer or a reception buffer, and the like. For example, a delay and a packet loss ratio measured as a result of an Real Time Transport Protocol (RTCP) which is a real time control packet transport protocol, or a result measured in an Medium Access Control (MAC) layer of a Wireless Local Area Network (WLAN) or a 3rd Generation Partnership Project (3GPP) RAN may be included in the network-aware information.
A method of expressing the network-aware information is already utilized. In general, network-aware information using the RTCP is currently used. However, because the RTCP measures a result generated based on a state of a lower layer such as a MAC/PHY layer, the RTCP has a long delay and a measured value may not be accurate in showing the network state. Accordingly, directly using MAC/PHY layer information is more efficient than using the currently used RTCP to obtain network-aware information. The MAC/PHY layer has a disadvantage of being a part of an entire end-to-end path, but whole service quality is determined by the last link quality, so that last link information is dominant. MAC/PHY layers such as layers using WiFi, 3G, 4G, and WiMAX which are widely used have a quite quick feedback and provide accurate information, but provided network-aware information has not been yet unified.
Therefore, a need exists for an apparatus and a method for effectively providing an adaptive multimedia service by unifying network-aware information through a definition of integrated abstract layer information and an expression method.
The above information is presented as background information only to assist with an understanding of the present disclosure. No determination has been made, and no assertion is made, as to whether any of the above might be applicable as prior art with regard to the present invention.